According to the Centers for Disease Control and Prevention in the United States, over one million Americans suffer a slip, trip, or fall injury every year. More than 17,000 people die annually from a slip and fall accident. Slip, trip, and fall injuries make up approximately 15% of all work-related injuries. There were 219,630 nonfatal falls, slips, and trips in workplaces in 2012, and 668 people experienced a fatal workplace fall, slip, or trip. Falls, slips, and trips are the second most common cause of work fatalities. Nearly 1,800 people die every year from falls and fall-related injuries in nursing homes across the United States. About 57% of fall injuries occur due to slipping, tripping, or stumbling and most of these falls occur at home—50% occur inside the home, and 24% occur around or close to the outside of the home. Over half of these fall injuries occurred on the floor or level ground. About 16% occurred on stairs or an escalator, 8% were associated with curbs and furniture, 29% occurred when an older adult was working around the house or yard, and over 20% occurred while the person was engaged in leisure activities. Adults over age 55 are more prone to slip and fall accidents. One in three people over age 65 falls every year—many times they are repeat falls. Falls are the most common cause of traumatic brain injuries. Falls are the leading cause of non-fatal medically treated injuries in the U.S. Falls cause approximately 8.9 million visits to the emergency room every year. Between 20% and 30% of people experience an injury after falling including lacerations, hip fractures, or head traumas.
Many of the above accidents occur due to slippery floors. In addition to being wet, floors can become slipperier after cleaning or polishing with conventional floor cleaning preparations. The degree of slipperiness of a floor is measured using scientific instruments that accurately determine the coefficient of friction (COF) on a scale of 0 to 1.00 with 0.50 or greater being an acceptable level of friction to prevent the great majority of potential slips. Most smooth floor surfaces that are not treated with anti-slip coatings will measure 0.20 to 0.35 COF, thus greatly increasing the probability of a slip and potential injury. To reduce this probability, anti-slip coatings can be applied to effectively increase the COF to safe levels, usually as dilute aqueous solutions that become effective upon drying at ambient conditions. Many anti-slip coatings are available as part of a detergent system that also cleans soiled floors, retards soil re-deposition and may also enhance gloss. However, many of these products are high in pH and contain volatile organics compounds of moderate to high toxicity that evaporate into the air as the anti-slip film dries. This evaporation can take up to several days to accomplish, thus resulting in long, slow human exposure to toxic vapors. The high pH of the residual film deposited on the floor presents a possible corrosivity issue with direct skin contact such as babies crawling, toddlers playing, dogs licking and people walking with bare feet on high pH coated floors. Indirect contact can occur when soles of shoes are touched during the process of removal from the foot. A third issue with most current coatings used as anti-slip agents is the toxic nature of the non-volatile compounds that create the dried anti-slip film. Some anti-slip agents are water soluble, synthetic polymers manufactured from petroleum based non-renewable raw materials that create pollution during manufacture, are not biodegradable and whose toxicity may have not have yet been determined. This combination of water solubility and potential toxicity allows the possibility spreading the anti-slip agent to areas where it may be more difficult to remove and where skin contact is possible, such as carpeting in the workplace, home, car, business establishments and restaurants.
Therefore, a need exists for an anti-slip floor coating that is effective in increasing the COF of floor surfaces to a minimum of 0.50, is neutral pH and not corrosive to skin, has no toxic volatile organic compounds and no toxic non-volatile compounds used as anti-slip agents, is manufactured from renewable resources and are biodegradable.
In addition to soil removal and anti-slip properties, it is important that an anti-slip detergent have antimicrobial disinfecting properties, to control the spread of infectious disease germs. While many anti-slip detergents contain surfactants with good antimicrobial properties when wet, these surfactants have little or no residual anti-microbial efficacy when dry. Therefore, some anti-slip detergents may contain residual germ killers such as Triclosan or other chemicals that contain organic halogen groups. These types of compounds are poisonous to germs, but may be cause the creation of “super bugs” similar to MRSA that have mutated to be resistant to compounds that kill germs via a poisoning mechanism.
The World Health Organization reported that of the 56 million reported deaths worldwide in 2012, 17% or 9.5 million deaths were attributed to infectious, communicable diseases. Deaths caused by infectious diseases in the United States in 2012 were placed at ˜400,000 with ˜100,000 being attributed to hospital acquired infections. Non-fatal bouts with infectious diseases are responsible for ˜3.4 billion sick days each year in the United States alone. Therefore, it is important to apply an effective anti-microbial agent to floor surfaces during the cleaning process that is non-toxic to humans and pets, environmentally friendly, naturally derived from renewable resources and will not create “super bugs”.
A wide range of natural organic compounds are used as antimicrobials. Organic acids are used widely as antimicrobials in food products, e.g. lactic acid, citric acid, acetic acid, and their salts, either as ingredients, or as disinfectants. For example, beef carcasses often are sprayed with acids, and then rinsed or steamed, to reduce the prevalence of E. coli. 
Traditional healers long have used plants to prevent or cure infectious disease. Many of these plants have been investigated scientifically for antimicrobial activity, and a large number of plant products have been shown to inhibit the growth of pathogenic microorganisms. Therefore, it is worthwhile to study plants and plant products, such as essential oils for activity against bacteria, viruses, fungi and mold.
An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds obtained from the leaves, bark, stems, flowers and berries of plants that particular aroma represents. Essential oils are also known as volatile oils, ethereal oils, aetherolea, or simply as the “oil of” the plant from which they were extracted, such as oil of thyme. An oil is “essential” in the sense that it carries a distinctive scent, or essence, of the plant, and not that it is essential to life.
Essential oils are generally extracted by distillation, often by using steam. Other processes include expression or solvent extraction, including supercritical CO2. They are used in perfumes, cosmetics, soaps and other products, for flavoring food and drink, for aromatherapy and as natural, renewable antimicrobials.
Many essential oils included in pharmacopoeias possess antimicrobial activity, including but not limited to: oils of bay, cedar, cinnamon, citronella, clove, eucalyptus, garlic, geranium, lavender, leleshwa, lemon, lemongrass, mint neem, black cumin, onion, oregano, peppermint, rosemary, sandalwood, sesame, tea tree and thyme.
Essential oils that are listed as edible include: almond oil (bitter), anise oil, bergamot oil, camphor oil, caraway oil, cassia oil, cedar leaf oil, cedarwood oil, cinnamon oil, citronella oil, clove oil, cornmint oil (Mentha arvensis), eucalyptus oil, geranium oil, grapefruit oil, lavender oil (spike), lemon oil, lemongrass oil, lignaloe (bois derose oil), lime oil, neroli (orange lower oil), nutmeg oil, onion and garlic oil, mint oil, orange oil, oregano oil, origanum oil, orris oil, palmarosa oil, patchouli oil, peppermint oil (Menthapzperita) pettigrainolpine oil, pine needle oil, rose oil (attar of roses), rosemary oil, sandalwood oil, sassafras oil, sesame oil, spearmint oil, thyme oil, vetiver oil, and ylang ylang oil.
Therefore, some of the essential oils that are both edible and have antimicrobial properties include cedar, cinnamon, citronella, clove, eucalyptus, garlic, geranium, lavender, lemon, lemongrass, mint, oregano, peppermint, rosemary, sesame and thyme oils and D-limonene.
D-limonene differs from essential oils in that it is a pure chemical compound whereas essential oils are mixtures of a plurality of usually similar compounds that vary in their concentration. Virtually all of the citrus essential oils contain some degree of D-limonene making it an essential oil component. Since D-limonene is a by-product of the orange juice industry, it is plentiful and considerably lower in cost than essential oils. Many industries are now using D-limonene as a low toxicity alternative to many non-polar solvents such as toluene, hexanes and heptanes.
Essential oils that are recognized by the US Environmental Protection Agency as minimum risk active pesticides under section 25(b) of the Federal Insecticide, Fungicide & Rodenticide Act (FIFRA) are cedarwood, cinnamon, citronella, clove, garlic, geranium, lemongrass, mint, peppermint, sesame, and thyme oils.
The antimicrobial properties of 21 essential oils and two plant essences were investigated against five food-borne pathogens. The maximum bacteriostatic concentration was 0.075%, with the oils of bay, cinnamon, clove and thyme being the most potent (ref: A. Smith-Palmer, J. Stewart and L. Fyfe. “Antimicrobial Properties of Plant Essential Oils and Essences Against Five Important Food-Borne Pathogens”, Letters in Applied Microbiology 1998. 26. 118-122).
Oil of thyme, the essential oil of the common herb thyme (Thymus vulgaris), contains 20-54% thymol. Thyme essential oil also contains a range of additional compounds, such as p-cymene, myrcene, borneol and linalool. Before the advent of modern antibiotics, oil of thyme was used to medicate bandages. Thymol, a powerful antiseptic, is the main active ingredient in various commercially produced mouthwashes. Thymol has also been shown to be effective against various fungi that commonly infect toenails. Thymol can also be found as the active ingredient in some all-natural, alcohol-free hand sanitizers and hard surface disinfectants such as Scotch-Brite Disinfectant Wipes where the active ingredient is 0.05% thymol as a component of thyme oil.
Microemulsion technology has been in existence for many years. In fact, many commercial microemulsion products are found in the marketplace, including beverages, personal care products, pesticide delivery systems, cutting oils and drug delivery systems.
Microemulsions are crystal clear because the micellar particle size is too small to scatter visible light. The IUPAC definition of microemulsion is “a dispersion of water, oil and surfactant(s) that is an isotropic and thermodynamically stable system with a dispersed domain diameter varying approximately from 1 to 100 nm, usually 10 to 50 nm.” In contrast to ordinary, white macroemulsions that usually require high shear conditions to form, micro-emulsions form upon simple mixing of the components, without the need for high-energy homogenization. Also, microemulsions of the present inventions are stable against phase separation and remain crystal clear in both concentrated and ready to use form.
The methods of the present invention produces novel, crystal clear, stable, oil-in-water microemulsions using mainly food grade or excipient grade surfactants, edible botanical extracts or essential oils, and water. No alcohols are used or needed to maintain stability The microemulsion compositions and the preparation methods thereof provide high manufacturing efficiency and yield with no by-products, low toxicity, low production cost, simple preparation process, good safety in production, storage, transportation and use process, good environmental protection performance, are biodegradable and have excellent antimicrobial efficacy and anti-slip floor coating properties.